Tension adjuster for slit metal sheets

ABSTRACT

This device for adjusting the tension of an initially tensionless sheet consisting of a plurality of slit strips in a sheet-mill, so that the tension applied to said sheet is distributed in a manner substantially proportional to the width of each slit strip, the speeds of said slit strips differing slightly from one another.

Umted States Patent 1 l 1 Gay [451 Aug. 22, 1972 [54] TENSION ADJUSTERFOR SLIT i [56] References Cited METAL SHEETS UNITED STATES PATENTS [72]Inventor 21 3,386,679 6/1968 Foulon et a1 ..226/195 x 2,292,851 I 8/1942Tykal ..226/ 185 X [73] Assignee: Compagnie des Ateliers et Forges de3,468,494 9/1969 Gaudin ..242/75.2 la Loire, Paris, France 3,111,28511/1963 =Coker et a1. ..226/ 195 X 3,547,332 12/1970 Gaudin ..242/75.2

[22] Filed: Sept 1970 Primary Examiner-Allen N. Knowles [21] Appl. No.:70,067 Attorney- Wehderoth, Lind, & Ponack [52] US. Cl. ..226/l9l,226/195, 242/752, I [57] CT 242/562 This device for adjusting thetension of an initially ten- 51 Int. Cl. ..B65h 23/18 sionless sheetconsisting of a plurality of slit strips ina 5 Fi f Search 22 95, 90 191192 193 sheet-mill, so that the tension applied to said sheet isdistributed in a manner substantially proportional to the width of eachslit strip, the speeds of said slit strips f differing slightly from oneanother.

5 Clains, 3 Drawing Figures PATENTED M1922 1972 SHEET 1 OF 3 PIERREANDRE GAY, I

Inventor llllluflh Attorneys PATENTEU 3.685, 71 l saw 3 0F 3 i PIERRE.HTDPE. GAY, v

Attorneys TENSION ADJUSTER FOR SLIT METAL SHEETS This invention relatesto slitting machines or slit lines of the type used for slittingsheet-mill products into narrow strips suitable for making miscellaneousarticles, v

and has specific reference to improved means for regulating the valueand distribution of tension of an initially tensionless sheet consistingof a plurality of. slit strips. r

It is known that the function of a slit line is to slit a relativelywide sheet or strip into a plurality of narrow strips. This linecomprises essentially an unrolling unit for uncoiling the continuouswide sheet, shear means for cutting this sheet into a plurality ofnarrow strips, and other means for coiling up the slit strips.

A hitherto unsolved problem arising in these slit lines is the propercoiling of slit strips. 7

In fact, before the slitting operation the sheet is neither perfectlyflat, nor of strictly uniform thickness. As a result, the slit stripshave neither constant lengths nor constant thickness.

Furthermore, to perform a satisfactory slitting operation the tractiveefforts exerted on the slit strips must be kept at avery low value justdownstream of the shearing means.

The problem of coiling slit strips is equivalent to the problem ofcoiling a plurality of unstressed strips having slightly differentthicknesses, which travel at slightly different speeds (these speedvariations being due to variations in length caused in turn by theinsufficient flatness of the initial wide sheet or strip) and have to becoiled under tension. In fact, a coil must compulsorily be formed undera certain stress in order to obtain a proper shape thereof and to avoidthe relative slipof its turns during the subsequent uncoiling thereof.

This invention is therefore concerned primarily with tension adjustmentmeans adapted to exert on an initially unstressed sheet consisting of aplurality of slit strips a tension which is distributed in a mannersubstantially proportional to the width of each slit strip, the

A typical form of embodiment of a tension adjuster I according to thisinvention will now be described by way of example with reference to theattached drawings in which FIG. 1 illustrates the pair of guide rolls;

FIG. 2 illustrates the pairr of braking rolls;

FIG. 3 illustrates the tension adjuster in the slitting line.

As illustrated in FIG. I, the guide rolls consist of a pair of shafts 12 mounted in bearings 3 and 4 respectively.

A series of rings 5 formed with relatively deep notches 6 are slipped onshaft 1, and adapted to be set in a variable position on said shaft 1 towhich they are secured by set screws 7.

Other rings 8 each provided with a disk 9 engaging one of said notches 6are slipped on the other shaft 2.

Thus, passages of adjustable width and each adapted to guide a slitstrip are formed between the guide rolls.

A typical slit strip is designated by the reference numeral 10.

adapted to be rotated about the axis of said pivot 12 by afluid-actuated cylinder 13.

The pair of braking rolls illustrated in FIG. 2 com prises a pair ofshafts l4, 15 carried by bearings l6, 17

: respectively.

A series of different and alternating rings 18. 19 are stacked on theseshafts l4, l5. Rings 18 are locked against rotation on shafts 14, 15 bysuitable key means. but adapted to slide axially therealong. These rings18 are locked in relation to the relevant shaft by a key groove 20formed in this shaft. The other rings 19 are free to rotate and moveaxially in relation to the shaft. These rings may advantageously becoated with resilient material such as rubber on their outer surface.The ring stacking is compressed between a fixed abutment 21 and amovableabutment22 constituting the piston of afluid-actuated cylinder 23.

The braking rolls are so driven that their peripheral speed is slightlyinferior to that of the strip. They can be urged towards each other byanother fluid-actuated.

' with a tension adjuster according to this invention.

After slitting the initial sheet the slit strips 'are coiled by acoiling machine 25 pulling these strips through the device of thepresent invention by extracting them from a loop pit 26.

What I claim is:

l. A device for adjusting the tension of slit strips comprising on theone hand a pair of guide rolls having shafts, one of said rollscomprising rings secured in an adjustable position on its shaft, saidrings having radial notches formed therein, the other of said rollscomprising rings slipped on its shaft each provided with a disk coactingwith one of said notches of said first named roll, the gap left betweensaid two rolls having the shape of a sequence of rectangles constitutingthe cross-sectional contours of the slit strips, said rolls being drivento have a substantially zero relative speed in relation to the stripand, on the other hand a pair of braking rolls comprising a series ofstacked rings, which are friction driven independently of each otherfrom a shaft rotatably driven at a speed so that if the rings do notslip on their friction surfaces their peripheral speed is inferior tothe strip speed.

2. A device for adjusting the tension of slit strips comprising a pairof guide rolls provided with adapters capable of giving to the gap leftbetween said two rolls substantially the shape of a sequence ofrectangles reproducing the succession of rectangles constituting thecross-sectional contours of the slit strips, said rolls move axially,and a second series of rings alternating with said first series of ringsadapted to rotate and move axially in relation to their shaft.

4. A device as set forth in claim 3, wherein said braking rolls arepressed against each other by a fluid-actuated cylinder.

5. A device as set forth in claim 3, wherein fluid-actuated cylindersare connected to said stacked rings to adjust the braking force.

1. A device for adjusting the tension of slit strips comprising on theone hand a pair of guide rolls having shafts, one of said rollscomprising rings secured in an adjustable position on its shaft, saidrings having radial notches formed therein, the other of said rollscomprising rings slipped on its shaft each provided with a disk coactingwith one of said notches of said first named roll, the gap left betweensaid two rolls having the shape of a sequence of rectangles constitutingthe cross-sectional contours of the slit strips, said rolls being drivento have a substantially zero relative speed in relation to the stripand, on the other hand a pair of braking rolls comprising a series ofstacked rings, which are friction driven independently of each otherfrom a shaft rotatably driven at a speed so that if the rings do notslip on their friction surfaces their peripheral speed is inferior tothe strip speed.
 2. A device for adjusting the tension of slit stripscomprising a pair of guide rolls provided with adapters capable ofgiving to the gap left between said two rolls substantially the shape ofa sequence of rectangles reproducing the succession of rectanglesconstituting the cross-sectional contours of the slit strips, said rollsbeing driven to have a substantially zero relative speed in relation tothe strip and a pair of braking rolls having a series of stacked ringsfrictionally driven independently of each other from a shaft rotatablydriven at a speed so that if the rings do not slip on their frictionsurfaces their peripheral speed is inferior to the strip speed.
 3. Adevice as set forth in claim 2, wherein said stacked rings comprise afirst series of rings stacked oN their shafts rotatably driven therefrombut adapted to move axially, and a second series of rings alternatingwith said first series of rings adapted to rotate and move axially inrelation to their shaft.
 4. A device as set forth in claim 3, whereinsaid braking rolls are pressed against each other by a fluid-actuatedcylinder.
 5. A device as set forth in claim 3, wherein fluid-actuatedcylinders are connected to said stacked rings to adjust the brakingforce.